Belt-pulley transmission

ABSTRACT

A drive system including a first rotary drive shaft, a pair of driven rotary half shafts and a pair of rotary jack shafts. The shafts generally parallel each other and the jack shafts are supported for independent swinging movement about the half shafts toward and away from the drive shaft. Longitudinally spaced portions of the drive shaft are drivingly connected to the jack shafts through drive belts trained about pulleys on the drive and jack shafts. The jack shafts are drivingly connected to the half shafts through drive chains trained about sprocket wheels on the jack and half shafts and brake means are operatively associated with the jack shafts for braking the latter when they are moved toward the drive shafts, which movement of the jack shafts simultaneously untensions the belts drivingly connecting the drive shaft to the jack shafts.

United States Patent Sanstrom 51 Jan. 25, 1972 [54] BELT-PULLEYTRANSMISSION 211 Appl. No.: 134,308

Related US. Application Data [62] Division of Ser. No. 766,078, Oct. 29,1968, Pat. No.

[52] US. Cl. ..74/217 R, ISO/6.2 [51] Int. Cl ..Fl6h 9/00, B62d 1 1/00[58] Field of Search ..74/217 R; ISO/6.2

[56] References Cited UNlTED STATES PATENTS Newhouse 180/61 PrimaryExaminer-Leonard H. Gerin Attorney-Clarence A. O'Brien and Harvey B.Jacobson [57] ABSTRACT A drive system including a first rotary driveshaft, a pair of driven rotary half shafts and a pair of rotary jackshafts. The shafts generally parallel each other and the jack shafts aresupported for independent swinging movement about the half shafts towardand away from the drive shaft. Longitudinally spaced portions of thedrive shaft are drivingly connected to the jack shafts through drivebelts trained about pulleys on the drive and jack shafts. The jackshafts are drivingly connected to the half shafts through drive chainstrained about sprocket wheels on the jack and half shafts and brakemeans are operatively associated with the jack shafts for braking thelatter when they are moved toward the drive shafts, which move ment ofthe jack shafts simultaneously untensions the belts drivingly connectingthe drive shaft to the jack shafts.

9 Claims, 9 Drawing Figures PATENTED JANZS I972 SHEET 2 OF Q 6mm H.Sansfrom INVENTOR.

BELT-PULLEY TRANSMISSION This application is a division of copendingapplication Ser. No. 766,078, now US. Pat. No. 3,595,332, forCrawler-Type Vehicle, filed Oct. 9, I968.

The vehicle of the instant invention is a crawler-type vehicle andincludes selectively drivable and breakable opposite side endless treadassemblies and is therefore drivable, steerable and breakable in thesame manner in which crawler-type tractors such as bulldozers aredrivable, steerable and breakable. Accordingly, the vehicle of theinstant invention is highly maneuverable, offers excellent drivingtraction and may be driven over substantially all types of unimprovedterrain.

The vehicle includes a main frame structure which may be of any suitableconfiguration depending upon the use to which the vehicle is to be putand the power and drive assemblies of the vehicle including the gearchanging, clutching and braking assemblies are carried by a subframewhich may be readily removed from the main frame for servicing andrepair and which is adjustable relative to the main frame from which theendless track members of the vehicle are supported whereby adjustment ofthe subframe relative to the main frame accomplish adjustment in thetensioning of-the endless crawler treads of the vehicle.

Although it is envisioned that the vehicle will have many uses intransporting personnel and materials as well as equipment over virginterrain, it is also to be understood that the vehicle will also beuseful wherever a lightweight crawler-type tractor may be utilized toadvantage.

The main object of this invention is to provide a crawler treadedvehicle of lightweight but rugged construction and which will be capableof supporting and transporting or towing other laden vehicle overunimproved terrain.

Another object of this invention is to provide a vehicle in accordancewith the preceding object and which includes structural featuresenabling ready adjustment of the endless crawler tread vehicle.

Still another object of this invention is to provide a vehicle includingan engine, transmission and clutch assembly as well as a brake assemblysupported from a subframe removably mounted on the main frame of thevehicle whereby necessary adjustments and maintenance or repairs may bereadily performed.

A final object of this invention to be specifically enumerated herein isto provide a vehicle in accordance with the preceding objects which willconform to conventional forms of manufacture, be of simple constructionand easy to use so as to provide a device that will be economicallyfeasible, long lasting and relatively trouble free in operation.

These together with other objects and advantages which will becomesubsequently apparent reside in the details of construction andoperation as more fully hereinafter described and claimed, referencebeing had to the accompanying drawings forming a part hereof, whereinlike numerals refer to like parts throughout, and in which:

FIG. I is a side elevational view of the vehicle;

FIG. 2 is a rear elevational view of the vehicle;

FIG. 3 is a top plan view of the vehicle;

FIG. 4 is a top plan view of the subframe of the vehicle from which thepower plant, transmission and braking and clutching mechanisms aresupported with portions of the power plant and controls for theclutching and braking assemblies broken away and illustrated inhorizontal section and the adjacent crawler tread portions of thevehicle illustrated in phantom lines;

FIG. 5 is a fragmentary vertical sectional view taken substantially uponthe plane indicated by section line 5-5 of FIG.

FIG. 6 is a bottom plan view of the central portion of the assemblageillustrated in FIG. 4;

FIG. 7 is a fragmentary vertical sectional view taken substantially uponthe plane indicated by section line 7-7 of FIG.

FIG. 8 is a fragmentary enlarged vertical sectional view takensubstantially upon the plane indicated by the section line 88 of FIG. 4;and

FIG. 9 is a schematic view of the drive train of the vehicle.

Referring now more specifically to the drawings the numeral 10 generallydesignates the vehicle of the instant invention which includes a mainframe referred to in general by the reference numeral 12. The main frame12 includes outer opposite side frame assemblies generally referred toby the reference numerals I4 including upper and lower longitudinallyextending members 16 and 18 as well as inner opposite side frameassemblies generally referred to by the reference numerals 20interconnected by means of transverse frame members 22 and 24. The inneropposite side frame assemblies 20 include lower longitudinally extendingangle members 26 and a plurality of longitudinally spaced andtransversely extending axle shafi members 28 are secured between eachpair of longitudinal members I8 and angle members 26. Each of the axleshaft members 28 has a support wheel 30 joumaled thereon and an endlessflexible track assembly referred to in general by the reference numeral32 is trained about each set of support wheels 30.

A plurality of support members such as upstanding support members 34, 36and 38 are secured between corresponding longitudinal members 16 and 18and a load supporting floor 40 is secured between the side frameassemblies 20. In addition, the main frame 12 includes transversemembers 42 and 44 secured between the outer opposite side frameassemblies 14 and also the inner opposite side frame assemblies 20.

With attention now invited more specifically to FIGS. 4-8 of thedrawings there may be seen a subframe generally referred to by thereference numeral 46. A motor referred to in general by the referencenumeral 48, see FIG. I, is mounted on an upper portion of the subframe46 and includes an output shaft 50 having a sprocket wheel 52 mountedthereon aligned with a torque input sprocket wheel 54 mounted on theinput shaft portion 56 of a suitable transmission referred to in generalby the reference numeral 58, such as a James transmission model 3R25available from the J. I. Edwins Co. Inc. of Issaquah, Washington. Anendless chain 60 drivingly couples the sprocket wheel 52 to the sprocketwheel 54 and the latter comprises a part of an integral manuallyactuatable clutch assembly 62 actuatable by lever 64, see FIG. 3. Thetransmission includes three forward speeds and one reverse speed and thegear changing of the transmission is accomplished through the shiftingof the gear shift lever 66, see FIG. 3.

The transmission 58 includes an output shaft 68 upon which a drivesprocket 70 is mounted and the drive sprocket is aligned with a drivesprocket 72 carried by a drive shaft 74 joumaled from the subframe 46.An endless flexible chain 76 drivingly couples the sprocket wheel 70 tothe sprocket wheel 72 and it may be seen that the drive shaft 74 isjoumaled from the frame 46 by means of journal blocks 78, see FIG. 6.

A pair of opposite side half shafts 80 and 82 are joumaled from thesubframe 46 by inner and outer journal blocks 84 and 86 and includedrive sprockets 88 on their remote ends, see FIGS. 4 and 6. The adjacentends of the half shafts 80 and 82 include driven sprockets 90 and a pairof jackshafts 92 and 94 are swingably supported from the subframe 46 bymeans of parallelogram arm assemblies 96, see FIG. 7. The opposite endsof each of the shafts 92 and 94 are swingably supported and joumaled bymeans of a pair of the parallelogram linkage assemblies 96 and eachassembly 96 includes a pair of parallel arm members 98 and 100 attachedat one pair of corresponding ends to a journal 101 on the correspondinghalf shaft and interconnected at their other pair of corresponding endsby means of a journal block 102. Each journal block 102 rotatablyjournals the adjacent end of the corresponding jackshaft and each arm 98has one end of a control rod 104 pivotally secured thereto. The controlrods I04 operatively associated with the jackshaft 92 have the otherpair of corresponding ends thereof pivotally secured to actuating leversI06 carried by a first operating shaft 108 joumaled from the rear of thecorresponding side of the subframe 46 and the rearward ends of thecontrol rods 104 operatively associated with the jackshaft 94 have theirrearward ends pivotally connected to similar actuating levers 110carried by an operating shaft 112 corresponding to the operating shaft108. The shaft 108 and 112 have operating levers 114 and 116 securedthereto which project rearwardly and upwardly from the rearward end ofthe subframe 46 and have the lower ends of a pair of control rods 118and 120 pivotally secured thereto. The upper ends of the control rods 1l8 and 120 pivotally secured thereto. The upper ends of the control rods118 and 120 are pivotally connected to actuating levers 122 and 124including handles 126 and 128 pivotally supported from the upper end ofa forwardly and upwardly inclined support 130 whose lower end is securedto the subframe 46 and braced relative to the latter by means of abracing member 132. From FIGS. 1 and 2 of the drawings it may be seenthat the control rods 118 and 120 comprise turnbuckle assemblies wherebytheir effective length may be adjusted and it may also be appreciatedthat oscillation of the levers 122 and 124 will cause oscillation of theshaft 108 and 112. Of course, as the shafts 108 and 112 are oscillated,the parallelogram linkage assemblies 96 will be oscillated therebycausing the jackshafts 92 and 94 to be oscillated. The jackshafts 92 and94 include sprocket wheels 136 and 138 aligned with the sprocket wheels90 carried by the half shafts 80 and 82 and a pair of endless flexiblechains 140 drivingly connect the sprocket wheels 136 and 138 to thesprocket wheels 90. In addition, the jackshafts 92 and 94 have multiplegroove pulleys 144 and 146 mounted thereon aligned with similar multiplegroove pulleys 148 and 150 mounted on the opposite ends of the driveshaft 74. A plurality of endless flexible belts 151 are trained aboutthe pulley wheels 144 and 148 and the pulley wheels 146 and 150 andthereby drivingly connect the opposite end portions of the drive shaft74 to the jackshaits 92 and 94 when the endless flexible belts 151 areproperly tensioned, either one, two, three or four belts 151 may be usedon each set of pulley wheels carried by the drive shaft and thejackshafts.

The pulley wheels 144 and 146 include fifth sheaves 152, see FIG. 8 anda pair of elongated flexible brake bands 154 are trained about the fifthsheaves 152 of the pulley wheels 144 and 146 and have their oppositeends secured to the subframe 46 by means of adjustable anchors 156.

The subframe 46 is supported from the main frame 12 in any convenientmanner and is shiftable longitudinally of the latter. The subframe 46includes outwardly projecting apertured lugs 158, see FIG. 4, throughwhich fasteners (not shown) are secured to maintain the subframe 46 inadjusted shifted position. The sprocket wheels 88 have the endless trackmembers 32 trained thereabout and the sprocket wheels 88 are drivinglyengaged with the endless track members 32. In addition, the journalblocks 86 are carried by support plates 160 and each support plate 160of the subframe 46 includes an outwardly projecting abutment 162 havinga threaded bore formed therethrough in which an adjusting bolt 164 isthreaded. A jamnut 166 is threadedly engaged on each bolt 164 forcooperation with the corresponding abutment 162 and the head 168 of eachbolt 164 abuttingly engages an abutment member 170 carried by thecorresponding longitudinal member 18 at its rearward end. Accordingly,in order to adjust the endless track members 32, the fasteners (notshown) secured through the mounting lugs 158 may be loosened and thebolt 164 may be turned after the jamnuts 156 have been loosened.Thereafter, the jamnuts 166 may again be tightened so as to retain thesubframe 46 in its adjusted position prior to the fasteners (not shown)being secured to the apertured mounting lugs 158.

The subframe 46 is removably supported from the main frame 12 andtherefore may be readily removed for maintenance or repair on the motor48, the transmission 58 or any of the drive components merely byuntensioning the endless track members 32 and lifting the subframe 46from the main frame l2.

In operation, after the motor 48 has been started, the clutch lever 64and shift lever 66 may be operated to place the transmission 58 in theproper gear. Then, as the clutch lever 64 is shifted to the clutchengaged position, the drive from the motor 48 to the half shafts and 82is established. If it is desired to declutch either the endless trackmembers 32, the corresponding lever of the control levers 122 and 124 ispulled rearwardly which will swing the corresponding jackshaft forwardlyand untension the associated belts 151. Further rearward movement ofthat control lever will of course shift the corresponding jackshaftfurther forwardly to frictionally engage the corresponding sheave 152with its brake band 154 to thereby brake the jackshaft and thecorresponding and endless tread member. Accordingly, the vehicle 10 notonly includes the clutch62 comprising an integral portion of thetransmission 58, but also a clutch and braking mechanism for each ofthejackshafts.

The foregoing is considered as illustrative only of the principles ofthe invention. Further, since numerous modifications and changes willreadily occur to those skilled in the art, it is not desired to limitthe invention to the exact construction and operation shown anddescribed, and accordingly all suitable modifications and equivalentsmay be resorted to, falling within the scope of the invention.

What is claimed as new is as follows: I

1. A drive system including a first rotary drive shaft, a pair of drivenrotary half shafts generally paralleling said drive shaft, and a pair ofrotary jackshafts generally paralleling said driven half shafts andsupported for selected independent swinging about the axes of rotationof said driven half shafts toward and away from said drive shafts,longitudinally spaced portions of said drive shaft and correspondingjackshafts including pulley means, endless flexible belts trained aboutsaid pulley means for drivingly connecting said spaced portions of saiddrive shafts to saidjackshafts, means drivingly connecting saidjackshafts to said half shafts, and brake means operatively associatedwith said jackshafts and operative to brake the latter in response toswinging of said jackshafts toward said drive shaft from a positionswung away from the latter with said belts tensioned.

2. The combination of claim 1 wherein said drive system includesparallelogram linkage means supporting said jackshafts for swingingmovement relative to said half shafts.

3. The combination of claim 1 wherein said means drivingly connectingsaid jackshafts to said half shafts includes aligned sprocket wheels onsaid jack and half shafts and endless chains trained about correspondingsprocket wheels.

4. The combination of claim 1 wherein said brake means includes a brakedrum mounted on each of said jackshafts for rotation therewith and aU-shaped stationarily supported brake band opening away from said driveshaft trained about the side of each brake drum adjacent said driveshaft.

5. A drive system comprising a rotary drive shaft, a rotary driven shaftspaced from and generally paralleling the drive shaft, a jackshaftgenerally paralieling said driven shaft and said drive shaft, meanssupporting the jackshaft for swinging movement about the axis ofrotation of said driven shaft and movable toward and away from the driveshaft, means drivingly connecting the drive shaft and jackshaft, meansdrivingly connecting the jackshaft to the driven shaft, and brake meansoperatively associated with said jackshaft and operative to brake thelatter in response to swinging of the jackshaft toward the drive shaftfrom a position remote from the drive shaft with the drive connectiontherebetween being maintained.

6. The structure as defined in claim 5 wherein said supporting means forthe jackshaft includes a parallelogram linkage means swingablysupporting said jackshaft for swinging move ment relative to the drivenshaft.

7. The structure as defined in claim 5 wherein said brake means includesa brake drum mounted on the jackshaft for rotation therewith, and astationarily supported brake band engaging the brake drum forfrictionally braking the jackshaft when it moves toward the drive shaft.

supporting the jackshaft includes a parallelogram linkage meansswingable supporting said jackshaft for swinging movement relative tothe driven shaft, said brake band being substantially U-shaped inconfiguration and opening away from the drive shaft whereby the bightportion of the brake band will frictionally engage the brake drum whenthe jackshaft is moved toward the drive shaft.

i l 1! '3 l

1. A drive system including a first rotary drive shaft, a pair of drivenrotary half shafts generally paralleling said drive shaft, and a pair ofrotary jackshafts generally paralleling said driven half shafts andsupported for selected independent swinging about the axes of rotationof said driven half shafts toward and away from said drive shafts,longitudinally spaced portions of said drive shaft and correspondingjackshafts including pulley means, endless flexible belts trained aboutsaid pulley means for drivingly connecting said spaced portions of saiddrive shafts to said jackshafts, means drivingly connecting saidjackshafts to said half shafts, and brake means operatively associatedwith said jackshafts and operative to brake the latter in response toswinging of said jackshafts toward said drive shaft from a posiTionswung away from the latter with said belts tensioned.
 2. The combinationof claim 1 wherein said drive system includes parallelogram linkagemeans supporting said jackshafts for swinging movement relative to saidhalf shafts.
 3. The combination of claim 1 wherein said means drivinglyconnecting said jackshafts to said half shafts includes aligned sprocketwheels on said jack and half shafts and endless chains trained aboutcorresponding sprocket wheels.
 4. The combination of claim 1 whereinsaid brake means includes a brake drum mounted on each of saidjackshafts for rotation therewith and a U-shaped stationarily supportedbrake band opening away from said drive shaft trained about the side ofeach brake drum adjacent said drive shaft.
 5. A drive system comprisinga rotary drive shaft, a rotary driven shaft spaced from and generallyparalleling the drive shaft, a jackshaft generally paralleling saiddriven shaft and said drive shaft, means supporting the jackshaft forswinging movement about the axis of rotation of said driven shaft andmovable toward and away from the drive shaft, means drivingly connectingthe drive shaft and jackshaft, means drivingly connecting the jackshaftto the driven shaft, and brake means operatively associated with saidjackshaft and operative to brake the latter in response to swinging ofthe jackshaft toward the drive shaft from a position remote from thedrive shaft with the drive connection therebetween being maintained. 6.The structure as defined in claim 5 wherein said supporting means forthe jackshaft includes a parallelogram linkage means swingablysupporting said jackshaft for swinging movement relative to the drivenshaft.
 7. The structure as defined in claim 5 wherein said brake meansincludes a brake drum mounted on the jackshaft for rotation therewith,and a stationarily supported brake band engaging the brake drum forfrictionally braking the jackshaft when it moves toward the drive shaft.8. The structure as defined in claim 7 wherein said drive connectionbetween the jackshaft and drive shaft includes pulley means and endlessflexible belt means entrained about said pulley means, said meansdrivingly connecting the jackshaft to the driven shaft includingsprocket wheel means on said jackshaft and driven shaft and endlesschain means entrained about corresponding sprocket wheel means.
 9. Thestructure as defined in claim 8 wherein said means supporting thejackshaft includes a parallelogram linkage means swingably supportingsaid jackshaft for swinging movement relative to the driven shaft, saidbrake band being substantially U-shaped in configuration and openingaway from the drive shaft whereby the bight portion of the brake bandwill frictionally engage the brake drum when the jackshaft is movedtoward the drive shaft.